Anime is a media, like Film, and has many genres inside of it from Magical Girl and Sci-Fi and Slice of Life and Drama.

I would recommend you to start with some classics like all of the the Ghibli movies, Evangelion, Cowboy Bebop (just in case you forget , Goldenboy, Great Teacher Onizuka, Princess Tutu and so on. I also suggest Eve no Jikan, but that's too new to be a classic.

Anime is a media, like Film, and has many genres inside of it from Magical Girl and Sci-Fi and Slice of Life and Drama.

I would records to start with some classics like all of the the Ghibli movies, Evangelion, Cowboy Bebop (just in case you forget , Goldenboy, Great Teacher Onizuka, Princess Tutu and so on. I also suggest Eve no Jikan, but that's too new to be a classic.

Well going from "Dark undertones, bleak themes. I would also really prefer something outer space based, generally sci fi based or mecha." What seems to tick all those boxes in one is:

Infinite Ryvius (26 eps) - basically a kinda "Lord of the Flies" in space, a group of 15-17 year olds end "stranded" on an advanced space ship trekking across the solar system where a whole lot happens But the main problem being a bunch of teenagers stripped of any sort of social structure, how do they save themselves from themselves? > good character development in this one.

A couple of good shorts in the area are (20minutes) Pale Cocoon and Hoshi no Koe

Mecha wise you could look at any Gundam series tbh. Though Gundam SEED would be my recommendation first (100 eps +specials if you got the time!) also Code Geass maybe a recommendation if you can deal with awesomeness, a train wreck of a plotline, and a number of characters you want to kill yourself just watching - very mixed bag a fish this one!

also Code Geass maybe a recommendation if you can deal with awesomeness, a train wreck of a plotline, and a number of characters you want to kill yourself just watching - very mixed bag a fish this one!

Series 1 of Code Geass was pretty good, but series 2 really jumped the shark. I'm not sure how much I could enjoy series 2 without the dumb banter I had on imageboards while it was airing.

More I enjoyed involving mecha: Full Metal Panic (somewhat), Escaflowne and Tengen Toppa Gurren Lagann. I have not seen it, but Bokurano had robots and was pretty dark if I remember correctly.

Just a month ago I was the exact same as you. What I would suggest watching from my limited pool of knowledge and based on what you are looking for would be first Death note and then Code geass. Death note is not based in out space or even the future but none the less is absolutely fantastic. Code geass is a bit more light hearted to begin with, but does also have some from bleak themes in terms of morality and if the ends justice the means, also has imo one of the greatest scenes I have seen in any form of media. If not the greatest.

Also one thing to add, do not just stick to one type of a show, I personally watched Code geass on the recommendation of a friend and then only wanted to watch shows like it, but I quickly found that there were many other great shows in different genres that I would not have though I would like, but ended up really enjoying.

But anyway to summarize , if you want something with a dark theme watch death note. The first half of the show is out of this world, second half not as much but still great.

One that I'm going through and enjoying right now is Guilty Crown. Pretty interesting sci fi series, with light use of mecha but not too much to deter me (not a fan of "pure" mecha animes)

“A fool is not a person who does not know something. Rather, a fool is a person who is given information but who chooses to ignore what he is given based on how he wants things to be, rather than how things are."

I've been out of the anime loop for a little bit, but here are my recommends:

"Lain" & "Boogiepop Phantom" - Dark and cerebral.

"Berserk" -Probably my favorite alltime, it is a European fantasy anime for most of the series, but gets pretty messed up Hellraiser style towards the end, and if you want to seriously damage yourself read the manga (f'ing craaaazy.) Bonus: I hear there are new ones coming out. The original series has one of the worst anime blueball endings of all time.

"Deathnote" - Really good, but (and I know how snobby this sounds) read the manga don't watch the anime. I couldn't stand the anime soundtrack. Something about the overly dramatic music and "action" sequences where the character is furiously writing in a notebook made me laugh every time.

"Shigurui" - pretty cool samurai anime that also has a pretty dark vibe going on. Bonus: It is on netflix.

"Evangelion" -Watch the new movies that are out / coming out instead of the classics. They are updated and way better imo. Downside: they are not all out yet, so you'll have to wait.

"Grave of the fireflies". If you want to kill to birds with one stone, watch this one. It will get you good feel for studio ghibli. Both classic and bleak.

A few not mentioned but worth checking out with links to series info and descriptions:

RahXephon A bit like Evangelion with a better conclusion. Mecha series with some cerebral elements.

Fullmetal Alchemist: Brotherhood There are two adaptations of this series out there and I think this is the better one. Does have some more comedic elements, but is a very serious and at times dark series at it's core. Great animation, story, and voice acting. One of my all time favorites.

Macross I know you said you already dropped Robotech, but if it was because of the dated animation I suggest you give it another try but watch the original. A true classic in the mecha genre and it (along with the original Gundam) really are the basis for all the other series that came after. Robotech is just Macross with an different script dubbed over the top of the original but avoid it. Find a subbed version.

I also second some of the other series already mentioned like Berserk, Cowboy Bebop, and Ghost in the Shell. This thread here contains a bunch of other recommendations of various genres so you may find some more in there. Also, if you watch some series you enjoy, you can go to myanimelist.net type in the title of the series, and it will give you a list of similar series you may enjoy under the "Recommendations" section. That is how I usually find new series to watch now.